Analytic and experimental electrical conductivity between the stratosphere and the ionosphere

Abstract

Data on atmospheric conductivity obtained experimentally in the altitude region between 35 and 80 km by use of rocket‐borne Gerdien condensers are presented. Analytic expressions based on ion equilibrium and ionization by cosmic rays only are derived for comparison. The experimental technique is described, and several factors that might influence the measurements are evaluated. There is good agreement between the measured and predicted values of negative conductivity at altitudes up to 50 km. Low conductivity values observed between 50 and 80 km are attributed to ionic diffusion to particulate matter, the reduction agreeing quantitatively with that calculated from present estimates of the radius and concentration of noctilucent cloud particles. It is suggested that meteoritic dust may be an important agent for electron destruction in the ionosphere.

Electrification in the Earth's atmosphere for altitudes between 0 and 100 kilometers

“…Also given are selected values. These are admittedly subjective estimates; in deriving them more weight has been given to direct deductions from atmospheric phenomena than to laboratory Although O-and, especially, 03-are the negative ions first formed by attachment, it appears [Reid, 1964;Bio•di, 1964;Branscomb, 1964] that charge transfer and ion-atom interchanges can lead to the emergence of more complex ions, such as NO•-and 08-. These may have large PIERCE electron affinities of the order of 3 to 4 ev; once created they are not easily destroyed, and it seems quite plausible that their concentrations will quickly build up to overshadow that of 05-.…”

“…Attachment to dust and nuclei to form large ions has also been neglected. This undoubtedly occurs in the troposphere and perhaps also at higher altitudes [Bourdeau et al, 1959;Whipple, 1964]. Both clustering and large-ion formation could be treadted by adding terms to the balance equations, as indicated by Pierce [1963], but these would then become immensely complicated and, since the additional rate coefficients required can scarcely even be estimated, the already grea•t uncertainties would be vastly multiplied.…”

Low-Frequency Electromagnetic Oscillations of the Earth-Ionosphere Cavity

“…) f4ch less data, but equally severe discrepenciesare to be found in the ion concentration estimates. (Bourdeau, 1959;Whipple, 1964. ) It is clear from the results shown in figures 3 and 14 that the ionization levels at around 40-50 KM are very important for the Schumann resonances, and yet we find thse estimates of ionization at these levels varying by a factor of 50:1.…”

A further note on terrestrial extremely low-frequency propagation in the presence of an isotropic ionosphere with an exponential conductivity-height profile

“…The cosmic rays represent an ionization source effective even at altitudes below the D layer. The calculated and measured atmospheric conductivity [Bourdeau, Whipple, and Clark, 1959] may be approximated by (7) with 0.0 -10 -•ø mho/m, z0 -50 kin, and fi -0.138 km -1.…”